This invention relates to water crafts, particularly small vessels such as sailboats and dinghies, and to the use of piezoelectric materials for generating electrical energy for use on such crafts.
The present invention has particular utility with regard to a problem particularly prevalent in small pleasure crafts, namely, the safe and efficient provision of electrical energy over extended periods of time during which only relatively small quantities of electrical power are required. For reasons of safety, all water crafts are required to, or at least sensibly should, carry navigation lights, that is, small lights designed not particularly for purposes of on-board illumination, but for rendering the crafts visible to other craft at night and in poor weather. Such lights consume energy over prolonged periods of time and, although of small wattage, do require significant amounts of electrical energy. The problem, particularly in small crafts where even a small motor generator is undesirable for reasons of cost, safety, space requirements, noise and the like, is that the only practical presently available source of electrical energy is the common lead storage battery. Such batteries, however, require re-charging or periodic replacement, and require, in the absence of on-board charging means, frequent interruptions in the otherwise continuous usage of the crafts. Also, even with small on-board motor generator means for trickle charging the batteries for maintaining them continuously charged, the need to carry fuel for the generator motor and the noise and fumes therefrom are generally objectionable.